1. (Industrial useful field)
This invention relates to a workpiece carrier means for a surface grinding machine which grinds a workpiece in between a pair of grinding wheels.
2. (Prior art)
Conventionally, in case of grinding many workpieces; for example, a so-called passing-through type carrier disc or a carrier belt always moving in a fixed direction has been installed, the workpieces have been consecutively loaded on the carrier means in turn to be fed to between grinding wheels in such a manner as passing through in a fixed direction, thus the grinding process has been completed while they have passed through and between the grinding wheels.
However, the workpiece itself can not be revolved during the grinding process in the foregoing passing-through type carrier means, so that it is hard to improve a finishing accuracy and moveover it is impossible to finish a ground surface more accurately by means of a cut-in motion of grinding wheel during grinding, i.e. by narrowing a distance between the grinding wheels during grinding.
As a countermeasure against the above trouble, there has been proposed a surface grinding machine disclosed in Patent Application (Kokai) No. 57-26905, in which a workpiece is loaded on a reciprocating plate and this plate is reciprocated through between grinding wheels while the workpiece is revolved, thus the grinding process being accomplished. In this method, however, the carrier means becomes too large and moreover only one workpiece can be ground during the grinding process.
3. (Object of the invention)
An object of the invention is to provide a workpiece carrier means, in which plural workpieces can be ground at a time while being revolved, a finishing accuracy can be improved further as compared with the passing-through type carrier means, and moreover plural workpieces can be loaded on a workpiece carrier in places simultaneously and securely.
In order to accomplish the above object, in this invetion; a revolving workpiece holder having plural workpiece pockets is revolvably installed at a tip end of a carrier arm, the carrier arm being equipped in a rockable manner within a range from a grinding position between grinding wheels to a setting position apart from the grinding wheels; an automatic limited revolution mechanism which stops a revolution of the workpiece holder at a specified angular spot in the setting position of said carrier arm, is equipped; a loading arm and an unloading arm which have plural workpiece suction members in an arrangement corresponding to a workpiece pocket arrangement at the specified angular spot, are equipped in a rockable manner; and plural workpieces are simultaneously loaded on and unloaded from the workpiece holder in the above setting position by means of the loading arm and the unloading arm.